Steam locomotives require water at such rates that the storage tank behind the locomotive was refilled at 100 mile interverals. one technique used was to place a long tank between the rails and the water the water would be scooped up as the locomotive passed over the tank. The water level of the locomotive storage reservoir is 4 meters above the water level on the rails. find the minimum speed at which the train could pass over the tank and lift water up to teh full 4 m height.
(hint: consider the locomotive to be stationary and neglecting all losses)